Generally, telemedicine is a term used to describe a type of patient care which involves monitoring of a patient's condition by a healthcare worker located at a healthcare facility which is remote with respect to the location of the patient. Telemedicine, if adequately employed, is capable of providing enormous benefits to society. One such benefit is that patients can be examined without having to travel to a healthcare facility. This feature is particularly important for patients who live in remote areas who may not be able to easily travel to the nearest healthcare facility, or who need to be examined by a healthcare worker located far away from the patient, in another state, for example.
Another benefit of telemedicine is that it is capable of allowing a patient to be examined more often than would be possible if the patient were required to travel to a healthcare facility due to the ease with which it can be administered. For example, if a patient's condition requires that measurements be taken several times a day, it would be impractical for the patient to travel to and from a healthcare facility each time a measurement needs to be taken. It probably would be necessary for the patient to be admitted to the healthcare facility. The use of telemedicine could allow these measurements to be taken at the patient's home while the healthcare worker observed the patient or the measurement data from the healthcare facility.
Another benefit of telemedicine is that it allows a patient to be examined in a more timely manner than if the patient was required to travel to the healthcare facility. This is important in urgent situations, such as when a patient's condition becomes critical and emergency procedures must be taken immediately.
Many various types of telemedicine systems are known. One example of such a system is disclosed in David et al., U.S. Pat. No. 5,441,047, issued Aug. 15, 1995, which discloses an ambulatory patient health monitoring system for monitoring a remotely-located healthcare patient from a central station. The system includes instruments at the remote location for measuring the medical condition of the patient. The medical condition may correspond to health parameters, such as heart rate, respiratory rate, pulse oximetry and blood pressure. The system includes a first audiovisual camera disposed at the patient location and a second audio-visual camera disposed at the central station. Audio and video information is transmitted between the patient's remote location and the central station via a communications network, such as an interactive cable television network. Patient data is transmitted between the patient remote location and the central station by a separate communications network, such as satellite, radio transmission or telephone lines. A display is located at the patient's remote location and at the central station to allow the patient and the healthcare worker to observe each other simultaneously.
One of the disadvantages of the system disclosed in the David et al. patent is that, although it refers to sending the information between the healthcare worker and the patient via various types of networks, the information sent from the patient's home will have to be formatted in accordance with a different communications protocol for each of these different networks. Therefore, although the David et al. patent refers to the capability of using different types of networks, the system disclosed in the David et al. patent is not "network-independent" because the data must be formatted in accordance with a particular protocol at the sending end and the formatting process will have to be reversed at the receiving end in a different manner for each type of network. At the very least, this will require different software and/or hardware at each end for each different transmission media used. Another disadvantage of the system disclosed in the David et al. patent is that the audio and video data are sent over one communications network and the patient data is sent over another communications network.
Another example of a telemedicine system is disclosed in Tamura, U.S. Pat. No. 5,434,611, issued Jul. 18, 1995. This patent discloses a telemedicine system having a two-way CATV network for transmitting images, voice and data between equipment located at the patient's home and equipment located at a medical office. Cameras are located in both the patient's home and in the medical office to provide return images between the doctor and the patient. In order for the doctor's terminal to communicate with the patient's terminal, the doctor's terminal sends a signal over a control line to the patient's terminal. A line controller then selects a communication channel for the session by selecting an unused channel in a multiple channel access (MCA) system. The terminals then automatically tune to the assigned communications channel and the information is communicated over the assigned channel between the patient and the doctor.
One disadvantage of the system disclosed in the Tamura patent is that any communication between the doctor and patient must be set up by sending a signal which the line controller detects. The line controller then selects an unused channel for the communication. It also appears that the signal must be initiated by the doctor because the text of the patent only describes the situation where the doctor sends the signal to initiate the session. In any event, the system requires that a direct connection be made between the patient's terminal and the doctor's terminal. No provision is made for allowing medical measurement data to be sent to the doctor's terminal without a direct connection being made between the patient's terminal and the doctor's terminal. Therefore, in accordance with the system disclosed in the Tamura patent, it would be impossible for information relating to the patient's condition to be sent by the patient's terminal to the doctor's terminal in the absence of a direct connection being made between the terminals, which requires that the doctor be present for the session.
It would be advantageous to provide a telemedicine system which would allow either a patient or a healthcare worker to initiate a diagnostic session to cause diagnostic measurements to be taken and sent to a location, such as a healthcare facility, where medical files could be automatically updated by the data. One advantage of such a system is that a healthcare worker would not have to administer a diagnostic session and, therefore, would not have to participate in the session. Another advantage of such a system is that medical files could be automatically updated without any action on the part of a healthcare worker being required. Furthermore, as the medical files are automatically updated, the patient's condition could be automatically monitored so that, in the event that the patient's condition falls below a predetermined level, remedial measures can be taken. It would also be advantageous to provide a telemedicine system which would allow video, voice and medical data to be integrated and sent over a single network.
Accordingly, a need exists for a telemedicine system which is network-independent and which is capable of allowing video, voice and data relating to the patient's condition to be integrated and sent from a remotely-located patient terminal to a healthcare facility without the necessity of a direct connection being set up between the patient and the healthcare worker.